Product highlights6-1/2" 2-way speakers (pair) Plus One+ polypropylene woofer cone with hi-roll rubber surround 1" textile, edge-driven dome tweeter with 3.0 dB level adjustment True Four Ohm Impedance technology speaker's 3-ohm impedance combines with speaker wire impedance for a 4-ohm load compatible with virtually all factory or aftermarket car stereos compatible with virtually all factory or aftermarket car stereos handles up to 60 watts RMS (180 watts peak power) frequency response: 53-21,000 Hz sensitivity: 93 dB at 2.83V top-mount depth: 2.063" grilles not included warranty: 1 year What's in the boxTwo 2-way speakers 2 Plastic mounting rings Eight 1" Screws Eight 1/2" Screws 8 Speed clips 2 Adhesive backed foam gaskets Instruction manual Template on box About this itemWritten by Crutchfield's Dave DelamereA modern classic Just as they were throughout my 16 years as a Crutchfield Advisor, Infinity's Reference Series speakers remain a popular choice for upgrading from factory speakers. The REF607F 6-1/2" 2-way car speakers follow that Infinity heritage by offering the killer combo of high efficiency and superb sound. Designed to work behind factory grilles, these Infinity speakers can liven up your music. Infinity's famous ingredients Reference Series speakers deliver powerful sound every mile you drive, thanks to oversized polypropylene woofer cones with durable hi-roll rubber surrounds. The cones move more air than other speakers of similar size, adding plenty of punch to the speaker's impressive performance. The 1" textile, edge-driven dome tweeters deliver clear and smooth highs, for a sound that's definitively Infinity. You can compensate for a less-than-ideal lower door location by raising the tweeter level by 3 dB to get more out of those higher frequencies. Excellent power-handling These speakers will blossom when powered by an external amplifier, but they're also sensitive enough to be a good match for a factory or aftermarket stereo. Plus, Infinity has come up with a safe way to get a little more power out of your system — these 3-ohm speakers work in combination with the speaker wire in your car so your car stereo sees a true 4-ohm impedance. Note: grilles are not included; these speakers are designed to fit behind factory grilles or panels in most applications. Optional grilles are available for custom installations.